Switch assembly for power and free conveyor



F. E. PEAN 3,443,525

SWITCH ASSEMBLY FOR POWER AND FREE CONVEYOR May 13, 1969 l of 2 7 Sheet Filed May 15, 1967 INVENTOR. FRED E.PEAN

ATTORNE Y5 May 13, 1969 E. PEAN 3,443,525

SWITCH ASSEMBLY FOR POWER AND FREE CONVEYOR FildMay 15,1967 sheet :2

\ INVENTOR.

FRED E.PEAN

A T'TORNE X6 United States Patent 3,443,525 SWITCH ASSEMBLY FOR POWER AND FREE CONVEYOR Fred E. Pean, Dayton, Ohio, assignor, by mesne assignments, to American Chain & Cable Company, Inc.,

New York, N.Y., a corporation of New York Filed May 15, 1967, Ser. No. 638,308

Int. Cl. B61k N00 US. Cl. 104-88 Claims ABSTRACT OF THE DISCLOSURE The power and free conveyor system described herein comprises a main track along which a plurality of trolleys are moved when engaged by a conveyor. In order to count the passage of trolleys past a predetermined point or to produce a signal as the trolley passes a point, a switch is mounted on the main track and includes a switch lever that has a first position and a second position. An actuator lever is pivoted on the main track in advance of the switch and projects into the path of the trolley so as the trolley moves along the main track, the actuating lever is engaged by the trolley to move the switch lever of the switch from the first position to the second position. A return lever is pivoted to the track beyond the switch and projects by gravity downwardly into the path of the trolley. When the trolley moves past the return lever, it swings the return lever to cause the return lever to engage the switch lever and return it to its first position.

This invention relates to power and free conveyors and particularly to a switch assembly for use in a power and free conveyor to produce an electrical signal or count.

Background of the invention In power and free conveyor systems wherein trolleys are moved along tracks, it is common to require that a count be taken of the passage of the trolleys past a predetermined point in order to prevent overloading of various portions of the system or to cause the trolleys to produce a signal for switchnig or other purposes. In either case, it is essential that false counts or signals be avoided. It has heretofore been suggested that an electrical switch be provided which is actuated by a trolley as it passes a point along the track. One of the problems with such a device is that vibration and the like tend to cause multiple counts or false signals.

Among the objects of the invention are to provide a power and free conveyor system wherein a count or signal can be positively produced by the passage of a trolley past a predetermined point; wherein multiple or false counts or signals are avoided; which is relatively simple in construction and easily maintained.

Summary The power and free conveyor system described herein comprises a main track along which a plurality of trolleys are moved when engaged by a conveyor. In order to count the passage of trolleys past a predetermined point or to produce a signal as the trolley passes a point, a switch is mounted on the main track and includes a switch lever that has a first position and a second position. An actuator lever is pivoted on the main track in advance of the switch and projects into the path of the trolley so as the trolley moves along the main track, the actuating lever is engaged by the trolley to move the switch lever of the switch from the first position to the second position. A return lever is pivoted to the track beyond the switch and projects by gravity downwardly into the path of the trolley. When the trolley moves past the return lever, it swings 3,443,525 Patented May 13, 1969 "ice the return lever to cause the return lever to engage the switch lever and return it to its first position.

Description of the drawings FIG. 1 is a partly diagrammatic side elevational view of a power and free conveyor system embodying the invention.

FIG. 2 is a part sectional view on an enlarged scale of the switch utilized in the system shown in FIG. 1.

FIG. 3 is a partly diagrammatic view on an enlarged scale of a portion of the system shown in FIG. 1.

FIG. 4 is a view similar to FIG. 3 showing the parts in a different operative position.

Description Referring to FIG. 1, the invention relates to a power and free conveyor system which comprises a main track 10 comprising inwardly facing channels along which wheeled carriers 11 are moved by a conveyor 12 that operates along a track 13. The carriers 11 may comprise spaced trolleys 14, 15 pivotally interconnected by a tie bar 16. One of the trolleys 14 is provided with a pusher lug 17 that is engaged by a pusher 18 on the chain 12 to push the trolley along the track in the direction of the arrow.

In order to produce a count or signal, as the carrier is moved along the track, a two-position switch 20 (FIG. 2) is provided on track 10 and includes a switch lever 21 that projects downwardly and has a roller 22 thereon. The two-position switch 20 can be of various constructions that are commercially available and in a first position has contacts out of contact and in second position may have contacts in contact.

An actuating lever 23 is pivoted to a bracket 24 mounted on the track 10 in advance of the switch 20. The actuating lever 23 includes a lower curved cam surface 24 and is normally yieldingly urged downwardly by a spring 25' interposed between the bracket 24 and lever 23 into the path of a portion of the carrier C and more specifically into the path of an actuating member 25 on the carrier. Spring 25 holds the upper end 23a of the lever against a surface 24a on bracket 24. The actuating lever 23 includes a flat upper cam surface 26 that is adapted to engage the roller 22 on the switch lever 21 when the actuating lever 23 is swung upwardly by engagement with a trolley to move the switch lever 21 from the solid line position to the broken line position as shown in FIG. 3.

A return lever 27 is pivoted to a bracket 28 on the main track 10 at a point beyond the switch 20. Lever 27 is normally biased by gravity so that it extends downwardly and forwardly into the path of the carrier C. In this position, it includes a lower downwardly and forwardly extending surface 29 and a generally vertical surface 30 which is adjacent the switch lever 21. As a carrier C passes the return lever 27 after engaging the actuating lever 23 and moving the switch lever to the second position shown in solid lines in FIG. 4, the return lever 27 is swung counterclockwise to the solid line position shown in FIG. 4 and causes the surface 30 to engage the roller 22 of the lever 21 and return the switch lever 21 and, in turn, the switch to the first position. The movement of the lever 21 between the first and second positions is facilitated by an over center spring arrangement such as is normally found in two-position switches, which tends to urge the lever and the contacts operated by the lever toward each of the two positions.

As discussed above, the switch 20 is a two position switch which may be of any conventional construction. Thus, as shown in FIG. 2, switch lever 21 rotates an actuator 31 to swing the switch plate 32 between two positions. In each of the positions, the switch plate completes a circuit to contacts 33, 34 or 35, 36. Depending upon the nature of the signal system, one or both sets of contacts may be electrically connected to produce a signal. In the system defined above, only the contacts 35, 36 are electrically connected to produce a signal. Other forms of two position switches can be used as will be apparent to persons skilled in the art.

The invention has been shown as used in connection with an accumulating trolley system wherein the accumulating machine 14a engages a cam surface 15a of a preceding trolley to lower the vertically movable pusher lug 17 and interrupt the movement of the trolley.

I claim:

1. In a power and free conveyor system, the combination comprising a main track,

a conveyor,

at least one trolley mounted for movement on said main track when engaged by said conveyor,

2. two-position switch positioned along said track and adapted to be actuated by said trolley to indicate the passage of said trolley past a predetermined point on said main track,

said two-position switch comprising a switch lever which in one position is in the path of the trolley and in a second position is out of the path of the trolley,

an actuating lever positioned along the path of said trolley and actuated by said trolley to move said switch lever from said first position to said second position,

and a return lever along the path of said trolley and actuated by said trolley to return said switch lever to said first position from said second position.

2. The combination set forth in claim 1 wherein said return lever is pivoted at a point beyond said switch and extends downwardly under the action of gravity into the path of the trolley,

said lever having a portion adjacent the upper end thereof adapted to engage said switch lever.

3. The combination set forth in claim 2 wherein said switch lever includes a roller adapted to be engaged by said actuating lever and said return lever.

4. The combination set forth in claim 1 wherein said actuating lever is pivoted in advance of said switch and has a lower cam surface engaged by said trolley and an upper cam surface adapted to engag said switch lever.

5. The combination set forth in claim 1 wherein said return lever is pivoted to said track at a point beyond said switch and is biased downwardly by gravity into the path of the trolley,

said return lever including a downwardly and forwardly extending cam surface adapted to be engaged by said trolley,

and a second surface adjacent the upper end thereof adapted upon swinging movement of said return lever to engage said switch lever and move said switch lever from said second position into said first position.

6. For use in a power and free conveyor system the combination comprising a main track, a conveyor, at least one trolley mounted for movement on said main track when engaged by said conveyor, the combination comprising a two-position switch adapted to be positioned along said track actuated by said trolley to indicate the passage of said trolley past a predetermined point on said main track,

said two-position switch comprising a switch lever which in one position is in the path of the trolley and in a second position is out of the path of the trolley,

an actuating lever adapted to be positioned along the path of said trolley and actuated by said trolley to move said switch lever from said first position to said second position,

and a return lever adapted to be positioned along the path of said trolley and actuated by said trolley to return said switch lever to said first position from said second position.

7. The combination set forth in claim 6 wherein said return lever is adapted to be pivoted at a point beyond said switch and extends downwardly under the action of gravity into the path of the trolley,

said lever having a portion adjacent the upper end thereof adapted to engage said switch lever.

8. The combination set forth in claim 7 wherein said switch lever includes a roller adapted to be engaged by said actuating lever and said return lever.

9. The combination set forth in claim 6 wherein said actuating lever is adapted to be pivoted in advance of said switch and has a lower cam surface engaged by said trolley and a upper cam surface adapted to engage said switch lever.

10. The combination set forth in claim 6 wherein said return lever is adapted to be pivoted to said track at a point beyond said switch and is biased downwardly by gravity into the path of the trolley,

said return lever including a downwardly and forwardly extending cam surface adapted to be engaged by said trolley,

and a second surface adjacent the upper end thereof adapted upon swinging movement of said return lever to engage said switch lever and move said switch lever from said second position into said first position.

References Cited UNITED STATES PATENTS 3,343,498 9/1967 Klamp l0488 a ARTHUR L. LA POINT, Primary Examiner.

DANIEL F. WORTH III, Assistant Examiner.

US. Cl. X.R. l04l72 

